Treeline along the Lena River,
Russia. Larch trees form the treeline in this part of Russia and have been used to
reconstruct surface air temperature variations stretching back centuries. Photo credit:
Glen MacDonald. Tree coring, Lena River, Russia. Tree-ring paleoclimatology
(ÒdendroclimatologyÓ) starts with the taking of straw-sized wood cores from individual
trees. In this way, the treeÕs paleoclimatic information can be extracted without harming
the tree. Each dendroclimatic record is based on the average signal obtained from cores of
20-30 trees. Photo credit: Glen MacDonald. Preparing for fieldwork, central Russia. Paleoclimatic research in
the Arctic is often difficult due to the absence of roads or airstrips. This means using
helicopters, boats, snow-mobiles and planes that can land on frozen lakes. This slide also
highlights the international coordination often needed to understand aspects of Arctic
environmental change. Photo credit: Glen MacDonald.
70°41'N 125°52'E
Reference: MacDonald et al., this paper
Proxy Type: tree-ring widths
Standardized climate record reflecting surface air temperature. Red indicates
temperatures greater than one standard deviation warmer than average for the reference
period (1901-1960), whereas dark blue indicates at least one standard deviation colder
than this average. All series presented as five-year averages (see paper for more
explanation).